With the scaling of integrated circuits, device applications have employed increasingly rapid speeds of operation. This places faster switching requirements on metal-oxide-semiconductor (MOS) devices. MOS field-effect transistors (MOSFETs) with thin silicon dioxide gate dielectric layers may demonstrate unacceptable gate leakage currents. High dielectric constants (k-values) for gate dielectrics are desirable for reducing gate leakage currents and increasing the switching speed of MOS devices. Where transition oxides have been used between a substrate and a high-k dielectric layer, the resulting film may exhibit an unreliable voltage threshold (Vt) when subjected to an applied field. Since conventional silicon oxide, which has a k value of about 3.9, cannot satisfy such requirements, high-k dielectric materials have been increasingly used.